1989 年 47 巻 1 号 p. 20-26
Polyfluoroaromatic compounds are now widely recognized as the important intermediates of bioactive materials and information recording media, because some of their fluorine atoms can be easily substituted to another functional groups by nucleophilic substitution reaction. However, as the effective fluorination method was not found, polyfluoroaromatic compounds were not yet produced in commercial scale. Among polyfluoroaromatic compounds, pentafluorobenzoic acid (PFBA) is an important raw material for photosensitive agents and bactericidal agents related to quinolone carboxylic acids.
In 1984, we established the full commercial scale technology to produce PFBA started from benzonitrile by 1) vapour phase chlorination to pentachlorobenzonitrile (PCBN), 2) halogen exchange reaction of PCBN to pentafluorobenzonitrile (PFBN), 3) hydrolysis of PFBN to PFBA.
This technology can be widely applied to production of tetrafluorophthalic acids, polyfluoropyridines and other polyfluoroaromatic compounds.
As many patents and technical papers related to application of polyfluoroaromatic compounds are published lately, our technology will be expected to extend to vaious fields in the near future.